Why doesnt my signal horn work? 1973 911T....

[jsoderbe]

Hi Guys,

I am trying to get my signal horn to work; I feel I have tried everything, now I think there is something stupid I am missing.

First: the signal horn works when I remove the steering wheel and ground the horn ring with the steering column. Then I install the steering wheel, without the pad, and it still works when I ground the button switch with the steering wheel mounting nut.

The button seems to work, I pulled it apart and the copper wire is connected to both sides.

But, when I install the horn pad nothing works. The pad is in excellent condition, all screws are tight.

Maybe I am getting the function wrong? Should the horn sound when I push the button switch, or should it ground with the steering wheel somehow? Or are the horn pads different from year to year?

My car is a 1973 911T Targa.

I hope my question make any sense....


Regards,

Johan

[Porboynz]

I think we need a photo because my 72 has a circular brass contact slip ring fixed to the column and then a spring loaded brass contact mounted into the steering wheel assembly that extends the circuit to the steering wheel. The steering wheel has a horn pad (large) that simply provides an earth when tilted/pushed. What's all this talk about a horn button?

[jsoderbe]

Sure, I am not sure about the US words for these parts....

Here are a few pics!

So this is the copper ring in the car, connected with the brown/white wire coming from the horn relay:



This is the spring loaded brass switch (which I call horn button):



This is the backside of the horn pad. I believe I am missing something here; there is no way this can ground the brown/white horn cable! The center has the rubber insulator, and the screws are insulated to make sure the spring doesnt ground into the steering wheel.



And this is the front side of the steering wheel:



And the back side:



So basically I believe my problem is that I cant figure out how pressing the horn pad can/will ground the brown/white cable....


Regards,

Johan

[911s55]

First of all, the turn signal cancelling plate/ring is mounted incorrectly. Unscrew it and rotate it 180 degrees so the portion sticking up is on the opposite side of the horn pin, or switch as you call it. The horn pin locates on the right side of the wheel, the cancelling protrusion on the left.

Also while it is off clean the brass plate and apply a very light coat of dielectric grease to it.

David

[jsoderbe]

Stupid, stupid, stupid me.... I knew it was something like this!

My steering wheel center was nice and powder coated black, so no chance of grounding there. I just had to sand the paint away to get the horn working.

You saying the horn pad should be grounding was a great help! Thanks!


Regards,

Johan

[Porboynz]

Make sure you fit the split cone shaped spacer on top of the spring correctly when refitting the wheel. It mounts opposite to what you think and I drove around for years grumbling about a small amount of up/down side to side movement in the stock steering wheel because I had that spacer around the wrong way. The cone shape goes into the steering column, its not to locate the spring as I had thought. I was all ready to rebuild the entire steering column when I saw a post detailing the correct orientation. Saved by the Pelican board.

[jsoderbe]

Thanks, so it is upside down on my steering wheel as shown on the above pics?

Johan

[Porboynz]

Sure looks like it. Look at the steering column, the bearing has a concave shaped mating surface. The spring pushes the cone shaped washer/spacer into that recess and holds the wheel firm. Does your wheel have a slight amount of play when assembled the way you have it? Try it with the washer/spacer reversed and voila!